// DuplicateRemoverPlugin.cs
// 
// Copyright © 2009 FreeZzaph
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
//

using System;
using System.Collections.Generic;
using System.IO;
using System.Security.Cryptography;

namespace LibFreeZzaph.DuplicateRemover
{
	
	public class DuplicateRemoverPlugin : IFreeZzaphPostProcessorPlugin
	{
		
		public string Name
		{
			get
			{
				return "duplicateremover";
			}
		}
		
		public string Action
		{
			get
			{
				return "Removing duplicate files";
			}
		}
		
		public IList<string> PerformPostProcessing(IList<string> files)
		{
			IList<string> hashList = new List<string>();
			IList<string> survivingFiles = new List<string>();
			
			SHA1 sha1 = SHA1.Create();
			foreach (string file in files)
			{
				byte[] fileContents = System.IO.File.ReadAllBytes(file);
				byte[] hash = sha1.ComputeHash(fileContents);
				string sHash = BitConverter.ToString(hash);
				
				if (hashList.Contains(sHash))
				{
					File.Delete(file);
				}
				else
				{
					hashList.Add(sHash);
					survivingFiles.Add(file);
				}
			}
			
			return survivingFiles;
		}
	}
}
